It's made out of lead, but it's safe unless you like to chew on your tools. You could also stick it in some sulfuric acid and charge your ipod.

For the past few years, I've been intermittently following the progress of Changing World Technologies (this isn't an advertisement, I swear). They build plants that use thermal depolymerization to turn organic waste from food process (like turkey offal) into heating oil.

I guess the trick is to make this energy efficient, but I'm not sure if they've actually achieved it. Seems like an interesting "green" thing to look into.

http://www.changingworldtech.com